Beam splice

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Thought I would see if anyone is experienced with beam splices. I need to splice together a w18x55 50' long. It needs to be spliced in the middle to get it in the building. It is not possible to use a crane or grade all.  I have the detail, calling for a 1/4 degree camber about 1 1/2". My question is about fabricating in the camber. My plan is to use steel sawhorses and get a nice level line with them. I will put 1 1/2" blocks in the center. The flanges will have standard 30 degree bevels, with a plate welded to one beam and bolted to the other at the web, like a moment frame.If I weld the plate on, then drill my holes and bolt together, do you think this will be sufficient enough to hold the camber while I finish the full pen weld on one flange? Or will it pull to much and will I have to do both full pen welds on the flanges at the same time?  Was planning on rolling beam so I don't have to weld through the mouse hole.  A steel backing bar will be tacked on as well.  Any help would be appreciated. Thanks.
Reply:Can't comment on the splice procedure but usually a camber is a sweep not an abrupt point isn't it. I'm not sure just asking....Mike
Reply:I’ve spliced a beam or two here and there. Can’t remember putting a camber in one tho. My first thought would be to splice the beams straight, and then heat shrink them to get the camber. Just guessing here, I think I would go with a double bevel open root for joint detail. Set your block in the center. Make one weld, move to the opposite side, and make that weld. Keep monitoring the beam after each weld. I’ve spliced a lot of beams with using a board at each end, and a string line to keep them straight. Main thing is skip around a lot, don’t put too much weld in one area. Attached ImagesDon’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:Beams are cold or heat cambered, heat for you unless you have a machine to bend them. You need a big rose bud ox propane or natural and a 1200 tempstick. 8" to zero triangles are soapstoned on beam every so many feet and heated and camber checked with a string and ruler. Takes a while sometimes a day with 2 men.We have cambered W 44x498 beams with 3-1/2 " camber. Beams are spliced with full pen welds and rat holes that are not filled up ,it creates a stress riser and will crack! You could do a bolted splice if PE designed it and approves it.
Reply:To the best of my knowledge, most cambered beams are bent to obtain the camber. The camber is usually there so the beam will sit level when the load is applied to the one side of it. It's going to be tough to obtain the true camber spec your looking for with splice welding in my opinion.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:To obtain somewhat of a camber the above mentioned is about the only way your going to get it, in my experience. Make sure when you fit the two together both cambers are facing up. As far as the bevel goes, if this is a structural piece and inspected, you will need a 45 degree bevel, 22.5 degrees on each flange and the web. You will need to rat hole the webs so you can run a bead along the inside as well after you back gouge. When you bevel the bottom of the beam bevel the inside so you never have to roll it. Its a pain in the rear but well worth it so you don't need to roll it. Leave your self an 1/8 in gap minimum between the beams and use a ceramic backing. If you are able to get a good enough root pass you wont need to back gouge the other side. Depending on the job will depend on if you need to fill the rat hole back up or not. If you do just use more ceramic as a backing and build your weld up, don't try and do it in one pass because its not going to work. Once you have everything CJP'd together and ground flush and pretty then drill your holes and bolt your plate then weld it in, if that where your plate is going. This is not a quick process but the steps you have to take IAW structural codes. I fabricate and weld structural everyday and this is the process we HAVE to do. Hope this helps and good luck.
Reply:Thank you akstructural the rathole will not be filled.  There is not true camber in the beam, the engineer just wants something in it for deflection.  It is roofload only.  About ceramic backing,  I've never used it.  How does it react with your root compared to 1/4" backer bar ? I will not be running in one pass.  I'm figuring 5 passes with .045 dual shield. I don't have the true details yet just a rough sketch. waiting on the true set just trying to get ahead of the game.
Reply:Benjie,       I'm curious. You have enough room inside this building to assemble a 50 foot beam and pick it up and install it in the ceiling but there isn't a hole in any of the outside walls (or you can't or are not permitted make one) that you could slide the whole 50 feet though in one piece. What kind of building is this? Or does it go far inside from an exterior wall?---Meltedmetal
Reply:Originally Posted by BenjieAbout ceramic backing,  I've never used it.  How does it react with your root compared to 1/4" backer bar ?
Reply:Melted metal buildings on three sides and power lines on the other.  The Project is on the 2nd floor,  no cranes allowed on the street there is just no way to get them on the second floor as full sticks.  Believe me I've looked at all possibilities.  I would rather not splice.
Reply:If it's a load bearing (sounds like it is if your cambering) beam, structural engineers have requirements all splicing is to be within 1/3 the length of the beam.  Suggest you get approval first (written) As for cambering, if its already 50 ft use heat and water till you get the results you need then cut and prep for a full pen weld. (if UT is being done after don't forget the mouse holes). You might be required to fish plate the webs (good idea any way - before UT, can't be done after). Alternate is to do a bolted connection (best solution) Hope this helps
Reply:As an engineer, I am not real enthused about splicing a beam in the center, because the center is the highest stress point. Splice plates would be mandatory, in my view.  From a design standpoint, you can't really assume that a weld is as strong as the base material.   Yes, a really good welder with a well controlled process can put in strong welds, but you still have a heat affected zone, residual stresses, many factors that could potentially weaken the weld or the area around the weld.Last edited by raferguson; 08-16-2015 at 05:46 PM.Reason: Added sentence about heat affected zone.Sculptures in copper and other metalshttp://www.fergusonsculpture.comSyncrowave 200 Millermatic 211Readywelder spoolgunHypertherm 600 plasma cutterThermal Arc GMS300 Victor OA torchHomemade Blacksmith propane forge
Reply:Originally Posted by rafergusonAs an engineer, I am not real enthused about splicing a beam in the center, because the center is the highest stress point.
Reply:Originally Posted by rafergusonAs an engineer, I am not real enthused about splicing a beam in the center, because the center is the highest stress point. Splice plates would be mandatory, in my view.  From a design standpoint, you can't really assume that a weld is as strong as the base material.   Yes, a really good welder with a well controlled process can put in strong welds, but you still have a heat affected zone, residual stresses, many factors that could potentially weaken the weld or the area around the weld.
Reply:Guess how many of these 36“ x 300# beams were spliced in the center? And we had a PE on site with us. Attached ImagesDon’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:Ceramic backing can be taken off unlike a backing, like when you certify. Its sole purpose is to "hold" your weld into place. Once you get your root pass in you can knock it off with your chipping hammer. It will not contaminate your weld. If you have never used it before do yourself a favor once you get it in place, it stays in place like 3M tape etc, use a piece of flat bar at each end and clamp it to the beam, ie beam, ceramic then flat bar, this will keep your wife from pushing it off. I will try and draw something up and add it in a few.
Reply:Originally Posted by BenjieMelted metal buildings on three sides and power lines on the other.  The Project is on the 2nd floor,  no cranes allowed on the street there is just no way to get them on the second floor as full sticks.  Believe me I've looked at all possibilities.  I would rather not splice.
Reply:Hope this helps. Don't laugh at my awesome drawing, Picasso I am not
Reply:Can the beam be flipped over to weld it? Would make it a lot easier. I'm curious why beams shouldn't be spiced in the middle. Pipes are essentially round beams and are spliced without any problems.
Reply:Thanks a lot for the help I am going to get some ceramic backing and give it a trial run. The cleanup looks nice for ut
Reply:This method used used mainly for field welding beams together in place. It eliminates overhead welding. One thing I forgot on my Picasso drawing is the rat holes on the top of the web as well so you can get in there with a die grinder and back gouge then weld. Make sure you stay in your puddle or you will have issues. Push your puddle and but stay in it. It will take some practice. The vertical up on the web will be the trickiest. Point your nozzle a little bit down into your puddle and push it into the ceramic instead of the normal nozzle up. When are you welding this?
Reply:Maybe next week or the week after just waiting on the final details
Reply:Originally Posted by AKSTRUCTUALThis method used used mainly for field welding beams together in place. It eliminates overhead welding. One thing I forgot on my Picasso drawing is the rat holes on the top of the web as well so you can get in there with a die grinder and back gouge then weld. Make sure you stay in your puddle or you will have issues. Push your puddle and but stay in it. It will take some practice. The vertical up on the web will be the trickiest. Point your nozzle a little bit down into your puddle and push it into the ceramic instead of the normal nozzle up. When are you welding this?
Reply:Just curious:Is NDT of any kind required after the weld is completed?
Reply:Yes utDid you get any practice runs in today using the ceramic?
Reply:Not yet today installed the 25' posts.  Welded to footing plates, welded top plates on.  welded bottom plates on 15' remaining post extension and drilled out to bolt together, ready to be cut to length.  Going to try to get ceramic backer tommorrow probably won't get to try it till this weekend.
Reply:Welding is always stronger than base metal. Camber in your case should be mill camber up!  Watch out clean every pass and you have to grind flush for ut. Rat holes are never filled ,it creates a stress riser and a cracking problem. The PE could design a bolted splice too ? ?
Reply:How did the splice and welding with ceramic go?
Reply:Got pulled off the job for a while.  finished up today 2 45' 18x55 spliced in the center carrying 2 55' 21x44  4 4x4x1/4" posts traveling through 3 floors to footings in basement.  project went really smooth full pen welds on flanges and sheer tabs welded to webs.  talked to inspector and backing bars could be left on for ut. passed 7 of 8 full pens had to grind one out problem at the root might have been traveling a bit slow on that one thanks for the replies. Still need to try ceramic backing sometime.
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Reply:I hate being the one to ask the stupid questions! I get it that weld is stronger than the metal. I've always been told welding robs strength from the adjacent metal. Is this not the case? A former neighbor told of his former job painting I beams after they were spliced. He knew nothing of the process, but said all very large section beams are joined together from shorter sections to make long ones. His life was mostly lived in a drug induced haze, so I never gave much credibility to the story. What's the real scoop?How is the rat hole filled when splicing?An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.
Reply:willie; never heard the weld removes strength from adjacent metal and the rat hole is used for welding access and is left open after the joint is done.i.u.o.e. # 15queens, ny and sunny fla
Reply:Originally Posted by BenjieGot pulled off the job for a while.  finished up today 2 45' 18x55 spliced in the center carrying 2 55' 21x44  4 4x4x1/4" posts traveling through 3 floors to footings in basement.  project went really smooth full pen welds on flanges and sheer tabs welded to webs.  talked to inspector and backing bars could be left on for ut. passed 7 of 8 full pens had to grind one out problem at the root might have been traveling a bit slow on that one thanks for the replies. Still need to try ceramic backing sometime.
Reply:Originally Posted by docwelderwillie; never heard the weld removes strength from adjacent metal and the rat hole is used for welding access and is left open after the joint is done.
Reply:Originally Posted by HT2-4956doc,This could get to be a complex subject quickly, so just a couple of broad general observations......For A36 grade structural steel (the most common grade out there and what most folks here are probably dealing with) well, it's pretty forgiving if you stick with 7018 (or equivalent strength) filler material.   But if you run stronger filler rod (80xx, 90xx or 110xx) you run the risk of cracking in the HAZ because the base material isn't strong enough to resist the shrinkage stresses from the weld puddle solidifying.   When you're dealing with a grade that gets it's strength from being quenched and tempered (T-1 or HY-80 for example) if you over heat the adjacent base material you can degrade it's strength by drawing down it's temper condition.   That's why not exceeding the maximum inter-pass temperature given on welding procedures for those materials is important to keep an eye on.Then there's the HSLA steels that get their strength from additional alloying elements that need special care and handling (like proper pre-heat temps and matching filler metal selection) to ensure sound welds of the proper strength.
Reply:@ HT2-4956 - +++.  Carbon steels, alloyed steels, stainless steels {especially}, aluminums {especially}, and other alloys are absolutely affected outside the FZ (fusion zone) into the HAZ.  In the HAZ is where corrosion loves to initiate, dwell, and wreak havoc for the joint unless metallurgical counter-measures are employed."Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi
Reply:Originally Posted by docwelderht2; i'm simply going from my humble high rise/fab shop experience; nothing fancy just hrms iron.
Reply:Originally Posted by BenjieGot pulled off the job for a while.  finished up today 2 45' 18x55 spliced in the center carrying 2 55' 21x44  4 4x4x1/4" posts traveling through 3 floors to footings in basement.  project went really smooth full pen welds on flanges and sheer tabs welded to webs.  talked to inspector and backing bars could be left on for ut. passed 7 of 8 full pens had to grind one out problem at the root might have been traveling a bit slow on that one thanks for the replies. Still need to try ceramic backing sometime.
Reply:I did leave the backing bars on.  My caps were all really close to to flush no grinding required. On this job I just tacked on the backing bars just in case I needed to remove them first time with this inspector. there was a different guy for fit up than ut.  I cut,operate heavy equipment, get it in the building 2nd floor and fit which is nice because I have control through the whole process which also keeps it interesting. No cranes makes you have to think. I could not disturb the 2nd floor made it chalenging